Police have ended a fourth investigation into alleged electoral fraud at the Peterborough by-election.

Cambridgeshire police has been investigating five allegations relating to the June 6 by-election which was won by Labour’s Lisa Forbes.

A polling station at City College Peterborough at the recent by-election

Officers have previously declared that no offences were committed in relation to one allegation of bribery and two relating to postal votes, and now a fourth allegation - the burning of ballots - has also led to the same conclusion.

This leaves just one outstanding allegation - a breach of the privacy of the vote.